Double-sided keyboard for use in an electronic device

ABSTRACT

A keyboard having a plurality of first keys on one side and second keys on the other, separated by a circuit board and a plurality of domes. The circuit board can be activated for entering information in an electronic device by pressing one or more keys on either side via the domes. The keyboard can be fixedly mounted on the cover of the electronic device such that the first keys can be used when the cover is closed and the second keys can be used when the cover is open. The keyboard can also be removably mounted so as to allow a user to change the keyboard side to be used. Alternatively, one side of the keyboard has a touch pad instead of keys.

[0001] This is a Continuation-In-Part application of co-pending U.S.parent application Ser. No. 09/702,539, entitled “Double-sided KeyboardHaving Two Keymats and One Activation Mat”, filed Oct. 31, 2000 andassigned to the assignee of the present invention.

FIELD OF THE INVENTION

[0002] The present invention relates generally to a keyboard in anelectronic device and, more particularly, to a double-sided keyboardhaving two keymats, or two sets of individual keys, located on bothsides of the keyboard for entering information into an electronicdevice.

BACKGROUND OF THE INVENTION

[0003] Man-machine interaction, in terms of user input, is of utmostimportance in portable communication devices. Splitting up one singlekeyboard into two or more sub-keyboards is one of the ways to improvethe efficient use of a communication device. For example, in aCommunicator, a phone keyboard can be used when the Communicatorfunctions as a telephone, and another separate QWERTY keyboard can beused when the Communicator is used for other functions. As portablecommunication devices become smaller and more compact, the availablespace and volume for two or more sub-keyboards becomes more limited.

[0004] It is desirable to provide a cost-effective method and apparatusfor entering information in an electronic device depending on thefunctions of the device.

SUMMARY OF THE INVENTION

[0005] According to the first aspect of the present invention, there isprovided a double-sided keyboard for entering information in anelectronic device. The keyboard comprises:

[0006] a circuit board having a first side and an opposing second side;

[0007] a first plurality of keys adjacent to the first side;

[0008] a second plurality of keys adjacent to the second side; and

[0009] a plurality of electrically conductive members disposed on thefirst side of the circuit board so that when at least one of the keys ispressed, at least one electrically conductive member is operativelyconnected to the circuit board for providing a signal indicative of theinformation for use in the electronic device.

[0010] Preferably, the electrically conductive members comprise aplurality of dome-shaped segments for making electrical contact with thecircuit board to activate the circuit board for providing the signals.

[0011] Possibly, the dome-shaped segments are shared with the first andsecond plurality of keys such that each dome-shaped segment can becaused to make electrical contact with the circuit board by either oneof the first plurality of keys or one of the second plurality of keys.

[0012] Alternatively, the electrically conductive members comprise afirst plurality of dome-shaped segments for making electrical contactwith the circuit board to activate the circuit board by pressing one ofthe first plurality of keys; and a second plurality of dome-shapedsegments for making electrical contact with the circuit board toactivate the circuit board by pressing one of the second plurality ofkeys.

[0013] Preferably, the first plurality of keys are capable of activatingthe circuit board only when the keyboard is oriented in a firstdirection, and the second plurality of keys are capable of activatingthe circuit board only when the keyboard is oriented in a seconddirection different from the first direction.

[0014] Preferably, the first plurality of keys are positioned above thecircuit board when the keyboard is oriented in the first direction, andthe second plurality of keys are positioned above the circuit board whenthe keyboard is oriented in the second direction.

[0015] Possibly, the electronic device comprises a device body having adevice connector and the circuit board comprises a circuit connector forelectrically connecting to the device connector for conveying the signalfrom the keyboard to the device body.

[0016] Possibly, the circuit connector is removable from the deviceconnector so as to allow the keyboard to be detached from the devicebody.

[0017] According to the present invention, the electrically conductivemembers are fixedly attached to the circuit board, or they are disposedon a mat disposed between the first plurality of keys and the circuitboard.

[0018] According to the present invention, the first plurality of keysare individually disposed or they are part of a keymat. Likewise, thesecond plurality of keys are individually disposed or they are part of afurther keymat.

[0019] Preferably, the electrically conductive members comprise aplurality of dome-shaped segments for making electrical contact with thecircuit board to activate the circuit board for providing the signal.

[0020] According to the second aspect of the present invention, there isprovided an electronic device including a device body having a bodydirection facing a user to allow the user to enter information in theelectronic device, the electronic device comprising:

[0021] a device connector disposed on the device body; and

[0022] a double-sided keyboard for entering the information, thekeyboard having a first side and an opposing second side, the keyboardcomprising:

[0023] a circuit connector;

[0024] a circuit electrically connected to the circuit connector;

[0025] a first user interface having a plurality of keys disposed on thefirst side of the keyboard;

[0026] a plurality of dome-shaped segments disposed between the keys andthe circuit, wherein when at least one of the keys is pressed, at leastone of the dome-shaped segments is deformed, causing the first userinterface to interact with the circuit for providing signals indicativeof the information;

[0027] a second user interface disposed on the second side of thekeyboard and capable of interacting with the circuit for providing thesignals, wherein the circuit connector is electrically connected to thedevice connector for conveying the signals from the keyboard to thedevice body when the keyboard is attached to the device body, and thekeyboard can be attached to the device body either

[0028] in a first position such that the first side is oriented in adirection substantially the same as the device direction so as to allowthe user to enter the information via the first user interface, or

[0029] in a second position such that the second side is oriented in adirection substantially the same as the device orientation so as toallow the user to enter the information via the second user interface.

[0030] Preferably, the second user interface comprises a plurality offurther keys, and wherein the further keys cause the circuit to makecontact with the dome-shaped segments for providing the signals when atleast one of the further keys is pressed, and the dome-shaped segmentsare electrically conductive for causing the circuit to provide thesignals when the deformed dome-shaped segment electrically contacts thecircuit.

[0031] Alternatively, the second user interface comprises a touchsurface which causes the circuit to provide the signals when pressure isasserted at a location of the touch surface.

[0032] Possibly, the dome-shaped segments are electricallynon-conductive, and when at least one of the keys is pressed, thepressed key asserts the pressure to the touch surface through thedeformed dome-shaped segment.

[0033] According to the third aspect of the present invention, there isprovided a double-sided keyboard removably attached to an electronicdevice to allow a user to enter information in the electronic device,the keyboard comprising:

[0034] a first side and an opposing second side;

[0035] a circuit connector;

[0036] a circuit electrically connected to the circuit connector;

[0037] a first user interface having a plurality of keys disposed on thefirst side of the keyboard;

[0038] a plurality of dome-shaped segments disposed between the keys andthe circuit, wherein when at least one of the keys is pressed, at leastone of the dome-shaped segments is deformed, causing the first userinterface to interact with the circuit for providing signals indicativeof the information;

[0039] a second user interface different from the first user interface,disposed on the second side of the keyboard, and capable of interactingwith the circuit for providing the signals, wherein the circuitconnector is electrically connected to the device connector forconveying the signals from the keyboard to the device body when thekeyboard is attached to the device body.

[0040] Preferably, the second user interface comprises a plurality offurther keys, and wherein the further keys cause the circuit to makecontact with the dome-shaped segments for providing the signals when atleast one of the further keys is pressed. The dome-shaped segments areelectrically conductive for causing the circuit to provide the signalswhen the deformed dome-shaped segment electrically contacts the circuit.

[0041] Alternatively, the second user interface comprises a touchsurface, which causes the circuit to provide the signals when pressureis asserted at a location of the touch surface.

[0042] Possibly, the dome-shaped segments are electricallynon-conductive. When at least one of the keys is pressed, the pressedkey asserts the pressure to the touch surface through the deformeddome-shaped segment.

[0043] The present invention will become apparent upon reading thedescription taken in conjunction with FIGS. 1a to 10 c.

BRIEF DESCRIPTION OF THE DRAWINGS

[0044]FIG. 1a is a diagrammatic representation illustrating a portableelectronic device having a set of keys on its cover.

[0045]FIG. 1b is a diagrammatic representation illustrating the sameelectronic device with the cover being opened to expose another set ofkeys.

[0046]FIG. 2a is a diagrammatic representation illustrating acommunication device having a set of keys on its cover.

[0047]FIG. 2b is a diagrammatic representation illustrating the samecommunication device with the cover being opened to expose another setof keys.

[0048]FIG. 3a is a cross sectional view illustrating the double-sidedkeyboard of the present invention, wherein the keys on both sides of thekeyboard share the same activation devices in order to activate thecircuit board.

[0049]FIG. 3b is a cross-sectional view illustrating the double-sidedkeyboard, wherein the keys on the two sides of the keyboard usedifferent activation devices to active the circuit board.

[0050]FIG. 3c is a cross-sectional view illustrating the double-sidedkeyboard, wherein some keys on both sides of the keyboard use the sameactivation devices but some keys use different activation devices toactivate the circuit board.

[0051]FIG. 3d is a cross-sectional view illustrating the double-sidedkeyboard of the present invention, wherein the keys on both sides of thekeyboard share the same activation devices in order to activate aconnection area integrated into a keymat.

[0052]FIG. 3e is a cross-sectional view illustrating the double-sidedkeyboard, wherein the keys on both sides of the keyboard use differentactivation devices to activate a connection area integrated into akeymat.

[0053]FIG. 3f is a cross-sectional view illustrating the double-sidedkeyboard, wherein some keys on both sides of the keyboard use the sameactivation devices but some keys use different activation devices toactivate a connection area integrated into a keymat.

[0054]FIG. 4a is a cross-sectional view illustrating two keys, whichshare a common activation device.

[0055]FIG. 4b is a cross-sectional view illustrating the activation ofthe circuit board by pressing the key on one side of the keyboard,wherein the keys on both sides share the same activation devices.

[0056]FIG. 4c is a cross-sectional view illustrating the activation ofthe circuit board by pressing the key on the other side of the keyboard,wherein the keys on both sides share the same activation devices.

[0057]FIG. 4d is a cross-sectional view illustrating the activation ofthe circuit board by pressing a key on either side of the keyboard,wherein the keys on different sides use different activation devices.

[0058]FIG. 5 is a schematic diagram illustrating the principle ofactivating the circuit board.

[0059]FIG. 6a is a diagrammatic representation of an electronic devicehaving a switching mechanism to define a keyboard mode when the cover isclosed.

[0060]FIG. 6b is a diagrammatic representation of the same electronicdevice, as illustrated in FIG. 6a, wherein the switching mechanismdefines another keyboard mode when the cover is open.

[0061]FIG. 6c is a diagrammatic representation of the same electronicdevice, as illustrated in FIG. 6a, wherein a directional switch is usedto further define the keyboard modes.

[0062]FIG. 7a is a diagrammatic representation of an electronic devicehaving a keyboard as an extended portion of the electronic device.

[0063]FIG. 7b is a diagrammatic representation of another electronicdevice having a keyboard as an extended portion of the electronicdevice.

[0064]FIG. 8a is a diagrammatic representation showing a removablekeyboard having two different user interfaces, according to the presentinvention.

[0065]FIG. 8b is a diagrammatic representation showing an electronicdevice having a device body for placing a removable keyboard, accordingto the present invention.

[0066]FIG. 8c is a diagrammatic representation showing the electronicdevice having thereon the double-sided keyboard, according to thepresent invention.

[0067]FIG. 8d is a diagrammatic representation showing the electronicdevice of FIG. 8c, wherein a different user interface is used forentering information.

[0068]FIG. 9a is a top view showing an electronic device having anexemplary user interface.

[0069]FIG. 9b is a top view showing the electronic device of FIG. 9awith a different user interface.

[0070]FIG. 10a is a cross-sectional view showing yet anotherdouble-sided keyboard, according to the present invention.

[0071]FIG. 10b is a cross-sectional view showing still anotherdouble-sided keyboard, according to the present invention.

[0072]FIG. 10c is top view showing the electronic device of FIG. 9a withyet another user interface.

DETAILED DESCRIPTION OF THE INVENTION

[0073]FIGS. 1a and 1 b illustrate a portable electronic device 100, suchas a personal digital assistant, which has a device body 102 and a cover104. When the cover 104 is in a closed position, it exposes a set offirst keys 12, as shown in FIG. 1a. When the cover 104 is in an openposition, it exposes a different set of second keys 22, as shown in FIG.1 b. The device body 102 has a display 106 to show information to theuser. It is understood that the cover 104 is electrically connected tothe device body 102 for allowing the keys 12 and 22 to provide signalsto the device body 102 for use in the device 100.

[0074]FIGS. 2a and 2 b illustrate a communication device 110, such as acommunicator device, which includes a phone keyboard having a pluralityof first keys 12, and a larger keyboard, such as a QWERTY keyboard,having a plurality of second keys 22. The communication device 110 has adisplay 122 to be used as a phone display when the cover 112 is in aclosed position, as shown in FIG. 2a. The communication device 110 alsohas another display 124 on the device body 114 to be used when the cover112 is an open position, as shown in FIG. 2b. It is understood that thecover 112 is electrically connected to the device body 114 for allowingthe keys 12 and 22 to provide signals to the device body 114 for use inthe device 110.

[0075] As shown in FIGS. 1a to 2 b, the first keys 12 and the secondkeys 22 are located on different sides of the cover 112. Preferably, thekey functions of the first keys 12 are different from the key functionsof the second keys 22. For example, the first keys 12 include numberkeys 0 to 9, a star key (*), and a pound sign (#), and the second keys22 include alphabetic keys. However, it is also possible that some orall of the first keys 12 have the same key functions as those of thecorresponding second keys 22.

[0076]FIGS. 3a-3 c are cross-sectional views of the double-sidedkeyboard 1 of the present invention. The double-sided keyboard 1 can beused on the cover 104 of the electronic device 100, as shown in FIGS. 1aand 1 b, or the cover 112 of the communication device 110, as shown inFIGS. 2a and 2 b. As shown in FIGS. 3a-3 c, the double-sided keyboard 1includes a circuit board 50 having a first side 52 and an opposingsecond side 54. Preferably, the circuit board 50 is a flexible printedcircuit board (PCB), printed wire board (PWB), or a flexible connectorarrangement, having electrical connection pads 60 for reading the keyinput on the first side 52. Flexible connector arrangements andelectrical connection pads 60 are well known in the art and are not partof the present invention. On the first side 52 of the circuit board 50,a plurality of dome-shaped, electrically conductive pads 44, is providedto make electrical contact with the electrical connection pads 60 on thecircuit board 50 so as to produce electrical signals. The dome-shaped,electrically conductive pads 44 can be individually and directlydisposed on the circuit board 50, as shown in FIGS. 4a-4 d. Theindividual pads 44 can be attached to the circuit board 50 with glues,tapes or by soldering, welding, or any other known attachmenttechniques. Alternatively, the electrically conductive pads 44 areproduced on a dome-sheet or activation mat 40, as shown in FIGS. 3a-3 f.The first keys 12 and second keys 22 can be individually keys, which arenot physically linked to each other. However, the first keys 12 can bephysically linked to each other by a first keymat 10, which is placed ontop of the activation mat 40, as shown in FIGS. 3a-3 c. Likewise, thesecond keys can be physically linked to each other by a second keymat20, which is placed below the activation mat 40, as shown in FIGS. 3a-3c. An actuator 30 is provided under each first key 12 so that when thefirst key 12 is pressed towards the circuit board 50, the correspondingdome-shaped, electrically conductive contact pad 44 is depressed by theactuator 30, causing the contact pad 44 to make electrical contact withis the corresponding electrical connection pad 60 (See FIG. 4b, wherethe electrical connection pad is represented by terminals 62, 64).Optionally, a mat cover 72 is provided over the first keymat 10 tophysically isolate one first key 12 from another. Likewise, when asecond key 22 is pressed towards the circuit board 50, the dome-shaped,electrically conductive contact pad 44 is depressed by a correspondingactuator 30, causing the contact pad 44 to make electrical contact withthe corresponding electrical connection pad 60 (See FIG. 4c, where theelectrical connection pad is represented by terminals 62, 64). Moreover,a mat cover 74 is provided over the second keymat 20 to physicallyisolate one second key 22 from another. Preferably, one or both of themat covers 72 and 74 can also serve as a mechanical support to the wholekeyboard arrangement, especially if individualy keys 12, 22 are usedinstead of the keymats 10 and 20.

[0077]FIG. 3a shows a double-side keyboard 1, wherein the first keys 12share the same dome-shaped, electrically conductive contact pads 44 withthe corresponding second keys 22. FIG. 3b shows a double-sided keyboard1, wherein the first keys 12 use different dome-shaped, electricallyconductive contact pads 44 from the second keys 22. FIG. 3c shows adouble-sided keyboard 1, wherein some of the second keys 22 of thesecond keymat 20 share the same conductive pads 44 with the first keys12 of the first keymat 10, and some of the second keys 22 use separateconductive pads 44.

[0078]FIGS. 3d-3 f are cross-sectional views of the double-sidedkeyboard 1′ of the present invention. The double-sided keyboard 1′ canbe used on the cover 104 of the electronic device 100, as shown in FIGS.1a and 1 b, or the cover 112 of the communication device 110, as shownin FIGS. 2a and 2 b. The double-sided keyboard 1′ is essentially thesame as the double-sided keyboard 1, as shown in FIGS. 3a-3 c, exceptthat the electrical connection pad 60 (See FIG. 4c, where the electricalconnection pad is represented by terminals 62, 64) and the necessaryconnection circuitry are integrated to the second keymat 20′. Thus, thesecond keymat 20′ also functions as a keyboard similar to the circuitboard 50 as shown in FIGS. 3a-3 c.

[0079]FIGS. 4a to 4 c are cross-sectional views illustrating theactivation of the circuit board by pressing a first key 12 or a secondkey 22, wherein the keys on both sides of the keyboard share the sameactivation devices. For illustrative purposes, the connection pad 60 onthe circuit board 50 is represented by two conductive terminals 62, 64provided under each dome-shaped, electrically conductive contact pad 44.It is preferred that a base support 32 is provided between the secondkey 22 and the circuit board 50 in the area around the terminals 62, 64.When the contact pad 44 is remote from the terminals 62, 64, as shown inFIG. 4a, the terminals 62, 64 act like an open switch. When the firstkey 12 is pressed towards the circuit board 50 along a direction denotedby an arrow 92 from its original position shown in phantom, the actuator30 depresses the dome-shaped, electrically conductive contact pad 44into contact with the terminals 62, 64, as shown in FIG. 4b. Theterminals 62, 64 act like a closed switch, wherein the terminals 62, 64are electrically connected. FIG. 4c shows that the terminals 62, 64 canalso be electrically connected when the second key 22 is pressed towardthe circuit board 50 along a direction denoted by an arrow 94 from itsoriginal position, shown in phantom. As shown in FIG. 4c, as the secondkey 22 is pressed along the direction 94, the base support 32 distortsthe flexible circuit board 50. The distorted circuit board 50, in turn,pushes the activation mat 30 40 towards the first keymat 10, depressingthe dome-shaped, contact pad 44 into contact with the terminals 62, 64.

[0080]FIG. 4d illustrates the activation of the circuit board 50 bypressing either a first key 12 on the first keymat 10 or a second key 22on the second keymat 20, wherein the keys 12, 22 use different contactpads 44.

[0081] In order to physically isolate the action of one dome-shapedcontact pad 44 from another, it is possible to provide a plurality ofspacers 34, as shown in FIGS. 4a-4 d.

[0082]FIG. 5 is a schematic diagram illustrating the principle ofactivating the circuit board 50 involving the terminals 62, 64. Asshown, the terminals 62, 64 act like a switch, which can be closed withthe electrically conductive contact 44. For example, the terminal 62 isconnected to the electrical ground G and the terminal 64 is connected toan output terminal O, which is connected to a voltage source having avoltage level V through a resistor R. When the terminals 62, 64 are notshorted by the contact 44, the voltage at the output terminal O is equalto or slightly lower than V. However, when the terminals 62, 64 areelectrically connected to each other by the contact 44, the outputterminal O is electrically grounded. Thus, when the contact 44 is causedto make contact with the terminals 62, 64, it provides a signal 130indicative of the voltage change at the output terminal O.

[0083] It should be noted that the connector arrangement on the circuitboard 50, as shown in FIGS. 3a-3 c and 4 a-4 d, is shared by both thefirst keymat 10 and the second keymat 20, but it is preferred that thekey functions of the keymat 10 and the keymat 20 are not the same.Because the same activation mat 40, or the like, can be pressed oneither side thereof, the electronic circuitry in the electronic devicethat uses the keyboard 1 should be able to recognize which one of thekeymats 10, 12 is being used. As shown in FIG. 6a, it is possible toinstall in the electronic device 100 a contact switch 130 which isoperatively connected to the cover 104 and the device body 102. Theswitch 130 is operable at two different states (open and closed, forexample) such that when the cover 104 is closed, as shown in FIGS. 1aand 6 a, the keyboard 1 (FIGS. 3a-4 d) functions in accordance with theinput from the first keys 12 of the first keymat 10. However, when thecover 104 is open, as shown in FIGS. 1b and 6 b, the keyboard 1functions in accordance with the input from second keys 22 of the secondkeymat 20. It is well-known that a mobile phone that has a phone coveruses an active flip or the like to connect and disconnect a phone call.A similar device can be used for the switch 130.

[0084] It is also possible to install on the cover 104 a device 132similar to a tilt switch or a gravity-sensitive switch, as shown inFIGS. 6b and 6 c, which can sense the direction of the cover 104regarding the gravity. With such a switch, the keyboard 1 can functiondifferently when the first keymat 10 is facing upward as opposed to whenthe second keymat 20 is facing upward. It is possible to choose theactive side by user selection.

[0085] If different detection areas are used for the first side and thesecond side, the pressed side and the key are clearly defined.

[0086] In FIGS. 1a, 1 b, 6 a-6 c, the double-sided keyboard 1 or 1′ isimplemented on a cover of an electronic device. It is possible that thedouble-sided keyboard 1 or 1′ is a non-movable part of an electronicdevice 120 or 122, as shown in FIGS. 7a and 7 b. As shown in FIG. 7a,the double-sided keyboard is an extended portion 105 of the device body102 of the electronic device 120, which includes a display 106. As shownin FIG. 7b, the double-sided keyboard is an extended portion 105 of thedevice body 103 of the electronic device 122, which has two displays 106and 107 corresponding to the keymats 10 and 12.

[0087] It should be noted that, as shown in FIGS. 4a-5, the dome-shapedcontact pad 44 is electrically conductive so that when the contact pad44 makes contact with the terminals 62, 64, it electrically connects theterminals. However, it is not necessary for the contact pad 44 to beelectrically conductive and for it to physically make contact with theterminals 62, 64 in order to activate the circuit board 50. For example,the contact pad 44 can be a poor electrical conductor, but it can causea change in the capacitance between the terminals 62, 64 when it is inclose proximity to the terminals 62, 64. This capacitance change can, inturn, cause a frequency change in a signal or other electricalcharacteristics of the signal in the circuit board 50. The activationmat 40 can be made of a variety of materials. For example, it can bemade of a non-conductive material and then made conductive by a flexiblemetal coating; it can be made from an inherently conductive polymermembrane such as polyacetylene, or it can be made of a polymer matrixembedded with a conductive filler, such as carbon or other metallicparticles. It is also possible that only the underside of thedome-shaped contact pad 44 is made conductive by having a flexible,conductive epoxy adhesive provided thereon, while the rest of theactivation mat 40 is electrically non-conductive. Furthermore, theresistor R in FIG. 5 can be the same in all keys 12, 22, but it can bedifferent in different keys.

[0088] The double-sided keyboard, according to the present invention,can be detached from the electronic device. As shown in FIG. 8a, thedouble-side keyboard 200 has thereon two different user interfaces. Thefirst user interface 210 includes a set of first keys 12 and the seconduser interface 220 includes a set of second keys 22, so that when thekeyboard 200 is attached to an electronic device 140, as shown in FIGS.8c-8 d, it turns the electronic device 140 into two different deviceswith different functions. The keyboard 200 also has a connector 202,which is engaged with a connector 150 on the electronic device 140, asshown in FIG. 8b, for conveying signals indicative of informationentered by a user using the keys 12 or 22. As shown in FIG. 8b, theelectronic device 140 has a device body 142, which has mounting grooves152 to secure the keyboard 200 when the keyboard is attached to thedevice body 140. The device body 142 has an upper side 144 facing theuser when the user enters information in the electronic device 140. Whenthe keyboard 200 is attached to the device body 142, either the firstuser interface 210 is exposed on the upper side 144 of the device body142, as shown in FIG. 8c, or the second user interface 220 is exposed onthe upper side 144, as shown in FIG. 8d. It is possible that theelectronic device 140 has a display 106 to show information to the user,and a set of common keys 146, which can be used for entering informationor for controlling the electronic device 140 regardless of which userinterface 210, 220 is exposed.

[0089]FIGS. 9a shows an exemplary layout of the user interface 210,which can be used as a phone keypad. FIG. 9b shows an exemplary layoutof the user interface 220, which can be used as a keypad for playingelectronic games on the electronic device 140. Not only can the userchange the keypad of a particular keyboard by switching the sides of thekeyboard, the user can user another keyboard on the same electronicdevice 140 as well. Thus, the double-sided keyboard 200 is used as aninsert or an accessory to the device body 142 to change the functions ofthe electronic device 140. For example, the user can insert anotherdouble-sided keyboard 300, as shown in FIGS. 10a and 10 b, onto the samedevice body 142. As shown in FIGS. 10a and 10 b, the double-sidedkeyboard 300 has a plurality of keys 12 on one side and a touch pad 310on the other side. When the keyboard 300 is inserted onto the devicebody 142 with the touch pad 310 exposed to the user, as shown in FIG.10c, the user can make drawings or control the electronic device 140′.

[0090] The double-sided keyboard 300 comprises a dome-sheet oractivation mat 40 and a circuit board 50 between the keys 12 and thetouch pad 310, as shown in FIG. 10a. The touch pad 310 can be made of anEMFI film (electromechanical film), for example, to allow the user toenter information in the electronic device 140′. As it is known, anelectromechanical film is a biaxially oriented plastic film containing apermanent electrical charge. When the film is deflected by touching, itproduces an electrical signal. Thus, with electrodes disposed on thefilm surfaces to convey electrical signals to a connector, theelectromechanical film can be used as a touch sensor. As with thekeyboard 200, as shown in FIGS. 3a-4 c, the user can press one or morekeys 12 to cause the corresponding electrically conductive sections 44to make electrical contact with the circuit board 50 in order to enterinformation in the electronic device 140′. The user can also enterinformation in the electronic device 140′ by using a finger, a pen or astylus to assert pressure on different locations on the touch pad 310.It is understood that the electrodes (not shown) on the touch pad areconnected to a connector 202 (FIGS. 8a) for providing touch pad signalsto the device body 142 (FIG. 8b).

[0091] Alternatively, the dome-sheet 40 is not actually for makingelectrical contact with a circuit board in the double-sided keyboard. Asshown in FIG. 10b, the dome sheet 40′ can be made of an electricallynon-conductive material just to give a tactile feel when the userpresses the keys 12. The actual sensing of the pressing of the keys 12is carried out by the touch pad 310. The touch pad 310 in FIG. 10bdetects the pressure on either side of the touch pad: the pressure onone side is asserted directly by a finger or a pen as with the touch padin FIG. 10a, whereas the pressure on the other side is asserted by thepressing of the keys 12.

[0092] It is also possible to replace the circuit board 50, as shown inFIGS. 3a-4 c, with a touch pad 310. Furthermore, the connector 202 ofthe keyboard 200 and the connector 150 on the device body 142 (FIGS. 8aand 8 b) can be a serial interface with a small number of pinssymmetrically arranged so that the keyboard 200 can fit both ways to thedevice body 142. A processor (not shown) in the device body 142 canrecognize whether the first user interface 210 or the second userinterface 220 is exposed for information entering. It is also possibleto use a resistive strip on the keyboard 200 and a number of pins on thedevice body 142 to input data from the keyboard 200 to the device body142. The present invention uses active domes 44 (electricallyconducting) or passive domes (electrically non-conducting) to facilitateinformation entering using a double-sided keyboard 200, 300. Theconveying of entered information from a removable keyboard 300 to adevice body 142 can be carried out by connectors, resistive strips orany other means. No particular method of conveying information ispreferred.

[0093] Thus, although the invention has been described with respect to apreferred embodiment thereof, it will be understood by those skilled inthe art that the foregoing and various other changes, omissions anddeviations in the form and detail thereof may be made without departingfrom the spirit and scope of this invention.

What is claimed is:
 1. A double-sided keyboard for entering informationin an electronic device, comprising: a circuit board having a first sideand an opposing second side; a first plurality of keys adjacent to thefirst side; a second plurality of keys adjacent to the second side; anda plurality of electrically conductive members disposed on the firstside of the circuit board so that when at least one of the keys ispressed, at least one electrically conductive member is operativelyconnected to the circuit board for providing a signal indicative of theinformation for use in the electronic device.
 2. The keyboard of claim1, wherein the electrically conductive members comprise a plurality ofdome-shaped segments for making electrical contact with the circuitboard to activate the circuit board for providing the signals.
 3. Thekeyboard of claim 2, wherein the dome-shaped segments are shared withthe first and second plurality of keys such that each dome-shapedsegment can be caused to make electrical contact with the circuit boardby either one of the first plurality of keys or one of the secondplurality of keys.
 4. The keyboard of claim 1, wherein the electricallyconductive members comprise: a first plurality of dome-shaped segmentsfor making electrical contact with the circuit board to activate thecircuit board by pressing one of the first plurality of keys; and asecond plurality of dome-shaped segments for making electrical contactwith the circuit board to activate the circuit board by pressing one ofthe second plurality of keys.
 5. The keyboard of claim 1, wherein thefirst plurality of keys are capable of activating the circuit board onlywhen the keyboard is oriented in a first direction, and the secondplurality of keys are capable of activating the circuit board only whenthe keyboard is oriented in a second direction different from the firstdirection.
 6. The keyboard of claim 5, further comprising a mechanism,operatively connected to the circuit board, for determining whether thekeyboard is oriented in the first or second direction and for providinga further signal indicative of the orientation direction for use in theelectronic device.
 7. The keyboard of claim 5, wherein the firstplurality of keys are positioned above the circuit board when thekeyboard is oriented in the first direction.
 8. The keyboard of claim 5,wherein the second plurality of keys are positioned above the circuitboard when the keyboard is oriented in the second direction.
 9. Thekeyboard of claim 1, wherein the electronic device includes: a movablecover for implementing said keyboard, and a device body mechanically andelectrically connected to the movable cover for allowing the circuitboard to convey the signal from the cover to the device body.
 10. Thekeyboard of claim 1, wherein the electronic device includes: a devicebody, and an extended portion for disposing said keyboard, wherein thedevice body is electrically connected to the extended portion forallowing the circuit board to convey the signal from the extendedportion to the device body.
 11. The keyboard of claim 1, wherein theelectronic device comprises a device body having a device connector, andthe circuit board comprises a circuit connector for electricallyconnecting to the device connector for conveying the signal from thekeyboard to the device body.
 12. The keyboard of claim 11, wherein thecircuit connector is removable from the device connector so as to allowthe keyboard to be detached from the device body.
 13. The keyboard ofclaim 1, wherein the electrically conductive members are fixedlyattached to the circuit board.
 14. The keyboard of claim 1, furthercomprising a mat disposed between the first plurality of keys and thecircuit board, wherein the electrically conductive members are attachedto the mat.
 15. The keyboard of claim 1, further comprising a matdisposed between the first plurality of keys and the circuit board,wherein the electrically conductive members are integrated with the mat.16. The keyboard of claim 1, wherein the keyboard further comprises afirst keymat for disposing the first plurality of keys.
 17. The keyboardof claim 16, wherein the keyboard further comprises a second keymat fordisposing the second plurality of keys.
 18. The keyboard of claim 17,wherein the circuit board is integrated into the second keymat.
 19. Thekeyboard of claim 17, further comprising a mat cover adjacent to thefirst keymat away from the first side of the circuit board forseparating the first plurality of keys.
 20. The keyboard of claim 17,further comprising a mat cover adjacent to the second keymat away fromthe second side of the circuit board for separating the second pluralityof keys.
 21. The keyboard of claim 17, wherein the electricallyconductive members comprise a plurality of dome-shaped segments formaking electrical contact with the circuit board to activate the circuitboard for providing the signal.
 22. The keyboard of claim 21, whereinthe dome-shaped segments are shared with the first and second pluralityof keys such that each dome-shaped segment can be caused to makeelectrical contact with the circuit board by either one of the firstplurality of keys or one of the second plurality of keys.
 23. Thekeyboard of claim 17, wherein the electrically conductive memberscomprise: a first plurality of dome-shaped segments for makingelectrical contact with the circuit board to activate the circuit boardby pressing one of the first plurality of keys; and a second pluralityof dome-shaped segments for making electrical contact with the circuitboard to activate the circuit board by pressing one of the secondplurality of keys.
 24. The keyboard of claim 17, wherein the electronicdevice comprises a device body having a device connector, and thecircuit board comprises a circuit connector for electrically connectingto the device connector for conveying the signal from a the keyboard tothe device body.
 25. The keyboard of claim 24, wherein the circuitconnector is removable from the device connector so as to allow thekeyboard to be detached from the device body.
 26. An electronic deviceincluding a device body having a body direction facing a user to allowthe user to enter information in the electronic device, the electronicdevice comprising: a device connector disposed on the device body; and adouble-sided keyboard for entering the information, the keyboard havinga first side and an opposing second side, the keyboard comprising: acircuit connector; a circuit electrically connected to the circuitconnector; a first user interface having a plurality of keys disposed onthe first side of the keyboard; a plurality of dome-shaped segmentsdisposed between the keys and the circuit, wherein when at least one ofthe keys is pressed, at least one of the dome-shaped segments isdeformed, causing the first user interface to interact with the circuitfor providing signals indicative of the information; a second userinterface disposed on the second side of the keyboard and capable ofinteracting with the circuit for providing the signals, wherein thecircuit connector is electrically connected to the device connector forconveying the signals from the keyboard to the device body when thekeyboard is attached to the device body, and the keyboard can beattached to the device body either in a first position such that thefirst side is oriented in a direction substantially the same as thedevice direction so as to allow the user to enter the information viathe first user interface, or in a second position such that the secondside is oriented in a direction substantially the same as the deviceorientation so as to allow the user to enter the information via thesecond user interface.
 27. The electronic device of claim 26, whereinthe second user interface comprises a plurality of further keys, andwherein the further keys cause the circuit to make contact with thedome-shaped segments for providing the signals when at least one of thefurther keys is pressed.
 28. The electronic device of claim 26, whereinthe dome-shaped segments are electrically conductive for causing thecircuit to provide the signals when the deformed dome-shaped segment iselectrically contacting the circuit.
 29. The electronic device of claim26, wherein the second user interface comprises a touch surface, whichcauses the circuit to provide the signals when the touch surface istouched.
 30. The electronic device of claim 26, wherein the second userinterface comprises a touch surface, which causes the circuit to providethe signals when pressure is asserted at a location of the touchsurface.
 31. The electronic device of claim 30, wherein when at leastone of the keys is pressed, the pressed key asserts the pressure to thetouch surface through the deformed dome-shaped segment.
 32. Adouble-sided keyboard removably attached to an electronic device toallow a user to enter information in the electronic device, the keyboardcomprising: a first side and an opposing second side; a circuitconnector; a circuit electrically connected to the circuit connector; afirst user interface having a plurality of keys disposed on the firstside of the keyboard; a plurality of dome-shaped segments disposedbetween the keys and the circuit, wherein when at least one of the keysis pressed, at least one of the dome-shaped segments is deformed,causing the first user interface to interact with the circuit forproviding signals indicative of the information; a second user interfacedisposed on the second side of the keyboard and capable of interactingwith the circuit for providing the signals, wherein the circuitconnector is electrically connected to the device connector forconveying the signals from the keyboard to the device body when thekeyboard is attached to the device body.
 33. The removable keyboard ofclaim 32, wherein the second user interface comprises a plurality offurther keys, and wherein the further keys cause the circuit to makecontact with the dome-shaped segments for providing the signals when atleast one of the further keys is pressed.
 34. The removable keyboard ofclaim 32, wherein the dome-shaped segments are electrically conductivefor causing the circuit to provide the signals when the deformeddome-shaped segment is electrically contacting the circuit.
 35. Theremovable keyboard of claim 32, wherein the second user interfacecomprises a touch surface, which causes the circuit to provide thesignals when the touch surface is touched.
 36. The removable keyboard ofclaim 32, wherein the second user interface comprises a touch surface,which causes the circuit to provide the signals when pressure isasserted at a location of the touch surface.
 37. The removable keyboardof claim 36, wherein when at least one of the keys is pressed, thepressed key asserts the pressure to the touch surface through thedeformed dome-shaped segment.